The oral administration route for medicamentous active substances, in particular solid active substances, is by far the most widely used. In fact, solid forms administered by the oral route are particularly suitable for ambulatory treatment, and this type of formulation usually offers a good stability with respect to time. However, this administration route, in which the active substance is administered by the buccal route, to be delivered into the stomach and the small intestine, has its limits, in particular because a large number of active substances are degraded in the gastrointestinal tract. As a result, it is often necessary to administer to the patient a dose of active substance which is considerably higher than the dose actually necessary for the activity of the product such as can be obtained by parenteral, intravenous, subcutaneous or intramuscular administration, for example, which leads to an increase in the volume of active substance to be administered. It is therefore necessary to manufacture considerably more active substance that is actually necessary in theory to obtain the desired therapeutic effect.
For this reason, new pharmaceutical forms are still being sought, in particular for active substances which are degraded particularly in the gastrointestinal tract.
Alternatives to parenteral administration, which involves sterile equipment and also aseptic conditions during the administration, which limits commercial distribution, are also still being sought.
Among the formulations suitable for ambulatory use, formulations for administration via the intermediary of the bucco-pharyngeal or nasal mucosa are also well known.
The formulations for the nasal route are generally intended for treatment of conditions of the nasal and rhinopharyngeal mucosa, and are thus essentially reserved for local treatment. This pharmaceutical form is rarely used for more general uses.
The formulations for the buccal route are generally intended for local treatment of conditions of the buccal mucosa, such as aphthae. This pharmaceutical form is also rarely used for systemic uses.
It would thus be desirable to have available an effective pharmaceutical formulation which is particularly suitable for ambulatory treatment, in particular suitable for medicaments which have a tendency to be degraded particularly by oral administration. Such a pharmaceutical formulation should cause neither irritation nor lesion of the mucosa.
Practice in the pharmaceuticals industry demands a large number of quality controls, and it would also be desirable if the nature of such a formulation is such that it does not interfere with direct assay of the active substance, such that it is easy to follow the product in a manufacturing chain or to identify the product. The phase of extraction of the active substance for its characterization would thus be avoided.
It would also be desirable to administer significant doses of active substances in volumes which are as reduced as possible.
In the majority of pathologies, it is desirable to obtain the fastest possible effect. For this reason, a particularly advantageous pharmaceutical formulation would be capable of achieving the fastest possible medicamentous effect, in addition with a good reproducibility of the administration.